A dilution series is a plurality of solutions which have been produced for a purpose from a concentrated starting solution as a result of dilution. These types of dilution series are produced, for example, in microbiology tor counting bacteria. In order to enable bacteria to be counted, neither too many nor too few bacteria must be cultivated. As a result of producing a dilution series, the original concentration of bacteria can be traced back from the diluted medium.
Diluter systems which absorb the sample into the dilater system and determine the volume of the dilution liquid by means of volume determining on a vacuum pump are known additionally from the prior art (see BioDiluter of July). These types of systems are very labor-intensive and time-consuming to clean and are consequently very expensive.
In order to enable precise determination of the number of bacteria, clean operation is necessary and all the parts which come into contact with the medium containing the bacteria have to be sterile. This results in very costly cleaning processes. In addition, homogeneous mixing of the sample with the diluent is important.